Phytases are well-known enzymes, as are the advantages of adding them to foodstuffs for animals, including humans. Phytases have been isolated from very many sources, including a number of fungal and bacterial strains.
It is an object of the present invention to provide alternative polypeptides having phytase activity and polynucleotides encoding the polypeptides. The polypeptides of the invention are preferably of amended, more preferably improved, properties, for example of a different substrate specificity, of a higher specific activity, of an increased stability (such as acid-stability, heat-stability, and/or protease stability, in particular pepsin stability), of an altered pH optimum (such as a lower, or higher pH optimum) and/or of an improved performance in animal feed (such as an improved release and/or degradation of phytate).